Affects of Varying Litter Types and Moisture on Soil pH Under Snowpack Colin Pettinati Winter Ecology Mountain Research Station 2014 University of Colorado, Boulder

Factors Controlling soil pH Parent Material Precipitation (moisture) Native Vegetation Crops grown Nitrogen input (i.e. fertilizer inputs) Burning Fossil Fuels Irrigation Water (Source 1)(Source 3)

Introduction Questions: How do different types of litter in 3 different vegetation types effect soil pH? Does soil moisture alter the soil pH?

Methods Designate 3 study areas, 1 Aspen stand, 1 Lodgepole Stand, and 1 Grass Meadow (2 of the 3 pits were also used for soil respiration- Scott Clingan) Dig 3 snow pits in each stand around 100cm Measure snow depth, soil temp at 0cm and 10cm, soil moisture, litter type and description, gather soil sample beneath litter Analyze the soil pH using soil pH kit

Site Locations Developed by Scott Clingan inc.

Site Characteristics Aspen Moisture: 4 across sites (Near Saturated) Litter: Deciduous leaves, grasses, woody debris Organic Matter: 4,4,5 Meadow Moisture: 3,2,1 (High, Moderate, Frozen Litter: mainly grasses, some deciduous leaves. Organic Matter Amounts: 3,3,3

Lodgepole Moisture: 2 across sites (Moderate Moisture) Litter: needles, cones, Lodgepole debris Organic Matter Amount: 5,5,4, Extremely thick, corky feel

Moisture vs pH F-statistic: 0.8808 P-value: 0.3792  No significance

Lodgepole/Aspen P= 0.000008 (significant) Meadow/Aspen P= 0.067368 (non significant) Meadow/Lodgepole P= 0.000003 (significant) F Value  212.3

Conclusion Moisture has little to no effect in the samples that I collected in the subalpine environment Litter type (dead organic matter) has a much more defining role in soil acidity; mainly in conifer stands

Further Questions for Research What mechanism or process is occurring within the conifer trees and litter that drops the acidity of the soil? Under what circumstances, if any, does moisture play an important role in soil acidity? How does the soil acidity under conifer stands effect the ecosystem in the surrounding area? Are lodgepole stands increasing another substance, such as nitrogen, that could possibly decrease pH?

Corrections Allow pH mixture to settle for longer The solution mixed needed to mix the soil and solution and the dark matter needed to settle in order to gain accurate measurements Sample more soil in each plot Sample more stands to cross sample

THANKS Y’ALL!!!

Sources USDA, NSF, NIFA, "Soils Part 4 ; Why does soil pH change?." Accessed March 7, 2014. http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447041&topicorder=6&maxto=10. 2. Jaeger , Charles, Russel Monson , Melany Fisk, and Steven Schmidt. "SEASONAL PARTITIONING OF NITROGEN BY PLANTS AND SOIL MICROORGANISMS IN AN ALPINE ECOSYSTEM." Ecology. no. 80 (1999): 1883-1891. 3. Michele Freppaz, Mark W. Williams, Timothy Seastedt, Gianluca Filippa, Response of soil organic and inorganic nutrients in alpine soils to a 16-year factorial snow and N-fertilization experiment, Colorado Front Range, USA, Applied Soil Ecology, Volume 62, November 2012, Pages 131-141, ISSN 0929-1393, http://0-dx.doi.org.libraries.colorado.edu/10.1016/j.apsoil.2012.06.006. (http://0-www.sciencedirect.com.libraries.colorado.edu/science/article/pii/S0929139312001503) Keywords: Snow; Soil; Nitrogen; Tundra

Acknowledgements Shout out to : Scott Clingan, Evan Esfahani, Derek Sweeney Special thanks and much appreciation to: Tim Kittel for an amazing experience and dedicating his time and knowledge